The impact of uncertainty resection on the prognosis of non-small cell lung cancer

Abstract

Objective: To explore the impact of uncertain resection on postoperative survival in non-small cell lung cancer. Methods: This is a retrospective cohort study. A retrospective analysis was conducted on the data of 477 patients with non-small cell lung cancer who underwent lobectomy in the Department of Thoracic Surgery, the Fourth Hospital of Hebei Medical University from December 2012 to December 2013. There were 302 males and 175 females, aged (59±8) years (range: 27 to 79 years). According to the surgical resection criteria issued by the International Association for the Study of Lung Cancer, the patients were divided into the intact resection group (R0 group, 286 cases) and the uncertain resection group (R (un) group, 191 cases). Clinical data between the two groups were compared using χ2 test, and propensity score matching (PSM) was performed on patients using the R language, with matching variables including gender, age, smoking history, adjuvant therapy, TNM stage, pathological type, and tumor site. The nearest-neighbor method was used for 1∶3 matching and the caliper value was 0.02. The survival curve was plotted using the Kaplan-Meier method and compared using the Log-rank test. The Cox proportional hazards regression model was used to identify risk factors in overall survival (OS). Subgroup analysis was based on TNM staging and mediastinal lymph node metastasis status. Results: In the R (un) group, 68 patients had positive lymph in the highest group and 129 patients did not undergo complete dissection of the mediastinal lymph nodes. The baseline data for the R0 group and the R (un) group were corrected using PSM, and a total of 369 patients were successfully matched, including 227 cases in the R0 group and 142 cases in the R (un) group. After PSM, the 5-year survival rates of the R0 group and the R (un) group were 64.3% and 52.1%, respectively (P=0.021). The 5-year survival rates of stage Ⅰ, Ⅱ, and Ⅲ patients were 85.2%, 65.9%, and 34.8%, respectively (P<0.01). TNM stage (χ2=46.913, P<0.01), pathological classification of adenosquamous cell carcinoma (HR=5.970, 95% CI: 3.117 to 11.431, P<0.01) and R (un) resection (HR=1.512, 95% CI: 1.065 to 2.147, P=0.021) were prognostic factors for postoperative survival. Subgroup analysis showed that in stage Ⅲ patients, 5-year survival rates of the R0 group and the R (un) group after resection were 45.8% and 9.5%, respectively (P=0.002). Among patients with mediastinal lymph node metastasis, 5-year survival rates of the R0 group and the R (un) group were 50.6% and 7.1%, respectively (P<0.01). Conclusions: TNM staging, pathological type, and R (un) resection are prognostic factors for overall postoperative survival in non-small cell lung cancer. In stage Ⅰ and Ⅱ patients, R (un) is not a prognostic factor for postoperative survival of non-small cell lung cancer. In patients with stage Ⅲ and mediastinal lymph node metastasis, R (un) is a prognostic factor for non-small cell lung cancer after surgery.